EP0067647A1 - Flocculant polymère cationique - Google Patents

Flocculant polymère cationique Download PDF

Info

Publication number
EP0067647A1
EP0067647A1 EP82302948A EP82302948A EP0067647A1 EP 0067647 A1 EP0067647 A1 EP 0067647A1 EP 82302948 A EP82302948 A EP 82302948A EP 82302948 A EP82302948 A EP 82302948A EP 0067647 A1 EP0067647 A1 EP 0067647A1
Authority
EP
European Patent Office
Prior art keywords
formaldehyde
bisphenol
polycondensate
dialkylamine
phenol
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
EP82302948A
Other languages
German (de)
English (en)
Other versions
EP0067647B1 (fr
Inventor
Katsutoshi Tanaka
Hisao Takeda
Mutsumi Kawano
Isao Miyahara
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Kyoritsu Yuki Co Ltd
Original Assignee
Kyoritsu Yuki Co Ltd
Mitsubishi Kasei Corp
Mitsubishi Chemical Industries Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Kyoritsu Yuki Co Ltd, Mitsubishi Kasei Corp, Mitsubishi Chemical Industries Ltd filed Critical Kyoritsu Yuki Co Ltd
Publication of EP0067647A1 publication Critical patent/EP0067647A1/fr
Application granted granted Critical
Publication of EP0067647B1 publication Critical patent/EP0067647B1/fr
Expired legal-status Critical Current

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F1/00—Treatment of water, waste water, or sewage
    • C02F1/52—Treatment of water, waste water, or sewage by flocculation or precipitation of suspended impurities
    • C02F1/54—Treatment of water, waste water, or sewage by flocculation or precipitation of suspended impurities using organic material
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
    • C08G73/00—Macromolecular compounds obtained by reactions forming a linkage containing nitrogen with or without oxygen or carbon in the main chain of the macromolecule, not provided for in groups C08G12/00 - C08G71/00
    • C08G73/02—Polyamines
    • C08G73/0206—Polyalkylene(poly)amines
    • C08G73/0213—Preparatory process
    • C08G73/022—Preparatory process from polyamines and epihalohydrins

Definitions

  • the present invention relates to a cationic polymer flocculant having excellent stability.
  • the polycondensate of epichlorohydrin and Mannich reaction products obtained by reacting three moles of formaldehyde and three moles of dimethylamine with one mole of phenol showed a conspicuous break down of the polymer molecule, particularly in an aqueous solution at a high temperature and at a low concentration.
  • the amount of polymeric cations was reduced to 38% by mole of the original amount.
  • polycondensates of an epihalohydrin and a mixture containing Mannich reaction product of a monohydric phenol and of a bisphenol at a specified ratio are excellent as flocculants and are less susceptible to deterioration, that is reduction of molecular weight.
  • the present invention provides a polycondensate, suitable for use as a cationic polymer flocculant, of (i) an epihalohydrin, (ii) a reaction product of a monohydric phenol with formaldehyde and a dialkylamine of two to six carbon atoms and (iii) a reaction product of a bisphenol with formaldehyde and a dialkylamine of two to six carbon atoms, the molar ratio of (ii):(iii) being from 90:10 to 50:50, preferably 85:15 to 50:50.
  • a preferred cationic polymer flocculant according to the present invention is a polycondensate of (i) an epichlorohydrin, (ii) a reaction product of phenol with formaldehyde and dimethylamine and (iii) a reaction product of 2,2-bis(4-hydroxyphenyl)propane with formaldehyde and dimethylamine, the molar ratio of (ii): (iii) being from 90:10 to 50:50.
  • the invention also provides a process for flocculating floculatable substances contained in industrial effluent, which comprises adding to said effluent an effective amount of flocculant comprising a polycondensate of the present invention.
  • the monohydric phenol for use as a starting material includes phenol and derivatives of phenol having a lower alkyl group of one to three carbon atoms on the benzene ring, such as cresol. Phenol is preferably used.
  • the bisphenol starting material is an alkylidenedi- phenol.
  • the bisphenol may be 2,2-bis(4-hydroxyphenyl) propane [so-called bisphenol A] or 2,2-bis(4-hydroxyphenyl) butane [so-called bisphenol B].
  • Bisphenol A is preferably used.
  • the reaction of the monohydric phenol or bisphenol with formaldehyde and a di-loweralkylamine is known as Mannich reaction.
  • the Mannich reaction involving the monohydric phenol can be carried out by known methods.
  • the reaction may be carried out by either adding the dialkylamine or formaldehyde to the phenol followed by the formaldehyde or dialkylamine respectively, or by reacting the dialkylamine with formaldehyde and adding this reaction mixture to the phenol [see "Organic Reactions Vol. I” (published by John Wiley & Sons in 1942)].
  • the Mannich reaction for the bisphenol can also be carried out in the same manner.
  • both the monohydric phenol and bisphenol as starting materials can be used in predetermined molar ratios.
  • the Mannich reaction product (ii) of the monohydric phenol and the Mannich reaction product (iii) of the bisphenol may be separately made and then mixed together.
  • the monohydric phenol can be mixed with the bisphenol and then this mixture is brought into reaction to obtain the mixed products of the Mannich reaction.
  • the Mannich reaction may occur.with at most 3 moles of formaldehyde and three moles of dialkylamine per mole of monohydric phenol.
  • the Mannich reaction may occur with at most four moles of formaldehyde and four moles of dialkylamine to per mole of bisphenol.
  • the amount of formaldehyde and the amount of dialkylamine introduced in the Mannich reaction may be in the range of equimolar to trimolar with respect to the monohydric phenol and may be in the range of equimolar to tetramolar with respect to the bisphenol.
  • the moles of formaldehyde and dialkylamine to be introduced are preferably as follows: and wherein X, Y, M and M 2 respectively represent the molar amounts of monohydric phenol, bisphenol, formaldehyde and dialkylamine.
  • dialkylamine Although formaldehyde and dialkylamine are used at about an equimolar ratio, one of them may be used in a little excess of the other. Instead of formaldehyde, a substance which generates formaldehyde such as paraformaldehyde may.be used.
  • the dialkylamine amines having a lower alkyl group of one to three carbon atoms are suitable. Dimethylamine,ethylmethylamine and diethylamine are preferable because of their reactivity. In addition, it is possible to use more than one of these amines in combination.
  • the molar ratio of monohydric phenol to bisphenol is preferably in the range of 90/10 to 50/50.
  • the molar ratio is 85/15 to 50/50.
  • the temperature of the Mannich reaction can be from 10 to 80°C, since at a lower temperature a longer reaction time is necessary and at a higher temperature, the dissipation by evaporation of dialkylamine and by-product formation are apt to occur, it is ordinarily preferable to carry out the reaction at 30 to 60°C for 3 to 6 hours.
  • reaction solvent water is ordinarily used. If necessary, an organic solvent miscible with water may be used.
  • dialkylaminomethylated monohydric phenol and dialkylaminomethylated bisphenol can be isolated. However, ordinarily, without being isolated they are respectively brought into polycondensation with epihalohydrin.
  • epichlorohydrin or epibromohydrin can be mentioned .
  • epichlorohydrin is ordinarily used, preferably in an amount of 0.7 to 2 times the molar amount of the sum of the monohydric phenol and the bisphenol. In the case of less than 0.7 times, a polymer having high molecular weight is not obtained. In the case of over twice, networks of three-dimensional structure are formed and the product readily becomes water-insoluble.
  • the reaction temperature of the polycondensation with epihalohydrin is preferably selected from the range of 10 to 90°C.
  • controllable temperature range is decided in accordance with the reactivity of the Mannich reaction products obtained by bringing three parts by mole of formaldehyde and three parts by mole of dimethylamine into a Mannich reaction with one part by mole of monohydric phenol and the product obtained by bringing four parts by mole of formaldehyde and four parts by mole of dimethylamine into a Mannich reaction with one part by mole of bisphenol A are highly reactive and, accordingly, it is necessary to carry out polycondensation at a temperature of lower than 40°C where the Mannich reaction product is reacted with an equimolar amount of epichlorohydrin.
  • reaction temperature is preferably controlled by adjusting the rate of addition of the epihalohydrin.
  • the solvent used for the polycondensation is not particularly restricted, the reaction is ordinarily carried out in an aqueous solvent as in the case of a Mannich reaction.
  • an acid is added to the reaction system at the time when the viscosity of the product has reached a desired value.
  • the acid may be added at the time when the Brookfield viscosity of the reaction mixture containing 50% by weight of the polycondensate becomes to higher than 1 Pa s (1000 cp), preferably, higher than 4 Pa s(4000 cp).
  • a mineral acid such as hydrochloric acid or sulfuric acid is preferably used in an amount which makes the pH of the reaction system less than 7.
  • the pH is more preferably reduced to below 4 from the view point of stability of the product.
  • the viscosity of the final product of polycondensation depends on the concentration of the polymer in the resultant reaction mixture, and in the case of concentration of the polymer of 45% by weight, the product showing a Brookfield viscosity of higher than about 0.1 Pa s (100 cp) (intrinsic viscosity, [ ⁇ ], of about 0.2 dl/g), more preferably, that showing Brookfield viscosity of higher than 0.8 Pa s (800 cp) (instrisic viscosity of 0.6 dl/g) is useful as a flocculant.
  • the flocculant according to the present invention have polymeric cations deteriorated less than the flocculant produced by only using the product of a Mannich reaction of phenol, and accordingly, it is the preferable flocculant.
  • the reason for suppressing the deterioration of the polymeric cations has not been elucidated, it is presumed that one reason is that the bisphenol prevents oxidation of the polymer.
  • a polymer having high molecular weight is obtained in polycondensation by adding the dialkylaminomethylated product of bisphenol.
  • the larger molecular weight of bisphenol is one of the reasons and that the bisphenol suppresses the break down of the molecular chain caused by the evolution of heat at the time of stopping the polycondensation by the addition of an acid.
  • the Mannich reaction products of one part by mole of phenol, three parts by mole of formaldehyde and three parts by mole of dimethylamine are polycondensed with epichlorohydrin and the polycondensation was stopped by hydrochloric acid at a Brookfield viscosity of 7.0 Pa s (7000 cp) of a condensation of polymer of 50% by weight in aqueous solution, the viscosity of the final product of the concentration of 45% by weight in aqueous solution was 0.8 Pa s (800 cp) Brookfield viscosity.
  • the flocculants according to the present invention exhibit very good effects when applied, for example, for removal of mud from river water; for acceleration of settlement of sludge in sewage treatment; for dewatering of such sludge; for treatment of oil-containing effluent derived from refining processes in the petrochemical industry; for acceleration of filtration of clay on production of cement; for concentration and filtration of porcelain clay slurry in the ceramic industry; for clarification of effluent from porcelain clay- treating processes; for dewatering of concentrate in the mining industry; for clarification of effluent from quarrying processes and also from coal dressing processes; for clarification of effluent from blast furnaces in the iron and steel industry and in the metal-working industry; for removal and settlement of mud from effluent derived from polishing processes; for settling and floating treatments of washings and oil-containing effluent from casting processes using cupola; for retention aid of dry or wet strength agent, drainage aid, for fixation of size, retention aid of pigment and filler in the paper-making industry, clarification
  • flocculants according to the present invention may be used together with other inorganic and/or organic flocculants.
  • Anionic and/or cationic polyacrylamide flocculants may be used in combination with the flocculants of the invention.
  • the viscosity of solution of the reaction product was 6.5 Pa s (6500 cp) at 25°C as determined by a Brookfield viscometer, corresponding to an intrinsic viscosity, [ ⁇ ], of 0.99 dl/g.
  • the viscosity of solution of the reaction product was 3.9 Pa s (3900 cp) at 25°C as determined by a Brookfield viscometer, corresponding to an intrinsic viscosity, [ ⁇ ], of 0.82 dl/g.
  • Each of the polycondensates prepared in Examples 1 to 4 and the Comparative Example was diluted with water to form an aqueous solution with a concentration of polymer of 0.5% by weight. After warming to 50°C for a predetermined time period, the amount of polymeric cation in the solution was determined by colloid titration at pH of 4 by using 1/400 N potassium polyvinylsulfate.
  • the results of the determination are shown in Table 1.
  • the amount of polymeric cation before heating is set at 100.
  • the product according to the present invention has a flocculating performance nearly equal to that of the product in Comparative Example.
  • Example 6 The test of Example 6 was repeated using the thus deteriorated polycondensate. The amount of polycondensate required to clarify the suspension was determined. The results are shown in Table 3.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Medicinal Chemistry (AREA)
  • Water Supply & Treatment (AREA)
  • Engineering & Computer Science (AREA)
  • Hydrology & Water Resources (AREA)
  • Health & Medical Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Environmental & Geological Engineering (AREA)
  • Polymers & Plastics (AREA)
  • Separation Of Suspended Particles By Flocculating Agents (AREA)
  • Treatment Of Sludge (AREA)
  • Processes Of Treating Macromolecular Substances (AREA)
  • Phenolic Resins Or Amino Resins (AREA)
  • Epoxy Resins (AREA)
EP82302948A 1981-06-09 1982-06-08 Flocculant polymère cationique Expired EP0067647B1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP88731/81 1981-06-09
JP56088731A JPS57204206A (en) 1981-06-09 1981-06-09 Cationic high molecular coagulant

Publications (2)

Publication Number Publication Date
EP0067647A1 true EP0067647A1 (fr) 1982-12-22
EP0067647B1 EP0067647B1 (fr) 1985-09-18

Family

ID=13951056

Family Applications (1)

Application Number Title Priority Date Filing Date
EP82302948A Expired EP0067647B1 (fr) 1981-06-09 1982-06-08 Flocculant polymère cationique

Country Status (6)

Country Link
US (1) US4370464A (fr)
EP (1) EP0067647B1 (fr)
JP (1) JPS57204206A (fr)
AU (1) AU546923B2 (fr)
CA (1) CA1166391A (fr)
DE (1) DE3266347D1 (fr)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
RU2162445C1 (ru) * 2000-06-28 2001-01-27 Акционерное общество закрытого типа "К-СТ Интернейшнл" Способ очистки технологических вод
RU2349695C1 (ru) * 2008-01-23 2009-03-20 ОАО "Санкт-Петербургский картонно-полиграфический комбинат" Способ подготовки оборотной воды картонно-бумажного производства к повторному ее использованию

Families Citing this family (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS58210919A (ja) * 1982-06-01 1983-12-08 Kyoritsu Yuki Kogyo Kenkyusho:Kk カチオン性ポリマ−の製造方法
JPH0372202U (fr) * 1989-11-10 1991-07-22
US5219914A (en) * 1989-12-27 1993-06-15 Rohm And Haas Company Cospray washout resistant roof mastic
US5837100A (en) * 1996-07-03 1998-11-17 Nalco Chemical Company Use of blends of dispersion polymers and coagulants for coated broke treatment
US6723207B2 (en) * 2002-08-05 2004-04-20 Johnsondiversey, Inc. Method of treating paper making rolls
WO2005113106A1 (fr) * 2004-05-07 2005-12-01 Profile Products L.L.C. Element de filtration environnemental en fibres composites contenant un floculant
US20060272789A1 (en) * 2005-06-02 2006-12-07 Steven Szep Method of treating papermaking fabric
US7897318B2 (en) 2007-11-29 2011-03-01 Lexmark International, Inc. Ionic polymer flocculants for the preparation of chemically processed toner
CN104023808B (zh) * 2011-12-28 2015-12-02 栗田工业株式会社 海水处理方法
CN117776363B (zh) * 2022-09-21 2025-09-09 中国石油天然气集团有限公司 一种聚磺体系废弃水基钻井液用絮凝剂及其制备方法

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4155847A (en) * 1977-08-24 1979-05-22 Mitsubishi Chemical Industries, Ltd. Cationic polymer flocculant prepared by reacting epichlorohydrin and a Mannich reaction product

Family Cites Families (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2695887A (en) * 1952-09-19 1954-11-30 Petrolite Corp Process for breaking petroleum emulsions
US2839500A (en) * 1953-01-26 1958-06-17 Petrolite Corp Gluconic acid salts of certain aminemodified thermoplastic phenol-aldehyde resins, and method of making same
US2997460A (en) * 1954-08-06 1961-08-22 Petrolite Corp Amine-modified thermoplastic phenolaldehyde resins and method of making same
US3038881A (en) * 1959-01-08 1962-06-12 Petrolite Corp Oxyalkylated phenol-aldehyde resins
CH584245A5 (fr) * 1973-02-14 1977-01-31 Ciba Geigy Ag
US3975305A (en) * 1975-06-27 1976-08-17 Nalco Chemical Company Ionene conductive polymers and resulting electrographic printing bases
US4038318A (en) * 1975-06-27 1977-07-26 Nalco Chemical Company Ionenes

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4155847A (en) * 1977-08-24 1979-05-22 Mitsubishi Chemical Industries, Ltd. Cationic polymer flocculant prepared by reacting epichlorohydrin and a Mannich reaction product

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
RU2162445C1 (ru) * 2000-06-28 2001-01-27 Акционерное общество закрытого типа "К-СТ Интернейшнл" Способ очистки технологических вод
RU2349695C1 (ru) * 2008-01-23 2009-03-20 ОАО "Санкт-Петербургский картонно-полиграфический комбинат" Способ подготовки оборотной воды картонно-бумажного производства к повторному ее использованию

Also Published As

Publication number Publication date
JPS57204206A (en) 1982-12-14
JPS6215242B2 (fr) 1987-04-07
AU7731581A (en) 1982-12-16
AU546923B2 (en) 1985-09-26
CA1166391A (fr) 1984-04-24
EP0067647B1 (fr) 1985-09-18
DE3266347D1 (en) 1985-10-24
US4370464A (en) 1983-01-25

Similar Documents

Publication Publication Date Title
US4155847A (en) Cationic polymer flocculant prepared by reacting epichlorohydrin and a Mannich reaction product
USRE28807E (en) Polyquaternary flocculants
USRE28808E (en) Polyquaternary flocculants
US3738945A (en) Polyquaternary flocculants
EP0067647B1 (fr) Flocculant polymère cationique
EP2274361B1 (fr) Polyamines cationiques fonctionnalisées et leur utilisation pour réduire la formation de ndma au cours du traitement de systèmes aqueux et applications à l'industrie du traitement des eaux, y compris les eaux résiduaires et potables
US3953330A (en) Water-soluble cationic polymeric materials and their use
US3784649A (en) High molecular weight ionene polymeric compositions
US3894946A (en) Process for treating industrial wastes
US4141827A (en) Process for clarifying coal wash waters
US3746678A (en) Amine-modified polyalkylene oxides
US4029708A (en) Linear surfactant polymers formed from substituted amines and difunctional reactants
US4308149A (en) Branched/cross-linked cationic phenol-formaldehyde polymers useful in wastewater treatment
US4267059A (en) Auxiliary for improving retention, dewatering and working up, particularly in the manufacture of paper
US4045377A (en) Cationic polymer prepared from dicyandiamide, a polyamide, a dialkylamine, and an epoxide
US4013606A (en) Process for preparing water soluble ionic polymers
US3894944A (en) Process for raw water clarification
US4631132A (en) Wastewater flocculating agent
US3894945A (en) Process for raw water clarification
US3498912A (en) Process for the clarification of waste effluents
US5659002A (en) Modified tannin mannich polymers
US4217215A (en) Process for flocculation using crosslinked polysulfonium compounds
JPS6324403B2 (fr)
US4217443A (en) Water-soluble crosslinked polysulfonium compounds and process therefor
JPS63218296A (ja) 活性汚泥のバルキング防止法

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

AK Designated contracting states

Designated state(s): BE DE FR GB NL

17P Request for examination filed

Effective date: 19830407

GRAA (expected) grant

Free format text: ORIGINAL CODE: 0009210

AK Designated contracting states

Designated state(s): BE DE FR GB NL

REF Corresponds to:

Ref document number: 3266347

Country of ref document: DE

Date of ref document: 19851024

ET Fr: translation filed
PLBE No opposition filed within time limit

Free format text: ORIGINAL CODE: 0009261

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT

26N No opposition filed
NLT1 Nl: modifications of names registered in virtue of documents presented to the patent office pursuant to art. 16 a, paragraph 1

Owner name: KYORITSU YUKI CO. LTD. EN MITSUBISHI KASEI CORPORA

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: GB

Payment date: 19990602

Year of fee payment: 18

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: FR

Payment date: 19990610

Year of fee payment: 18

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: DE

Payment date: 19990614

Year of fee payment: 18

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: NL

Payment date: 19990628

Year of fee payment: 18

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: BE

Payment date: 19990819

Year of fee payment: 18

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: GB

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20000608

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: BE

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20000630

BERE Be: lapsed

Owner name: MITSUBISHI CHEMICAL INDUSTRIES LTD

Effective date: 20000630

Owner name: KYORITSU YUKI CO. LTD

Effective date: 20000630

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: NL

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20010101

GBPC Gb: european patent ceased through non-payment of renewal fee

Effective date: 20000608

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: FR

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20010228

NLV4 Nl: lapsed or anulled due to non-payment of the annual fee

Effective date: 20010101

REG Reference to a national code

Ref country code: FR

Ref legal event code: ST

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: DE

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20010403